


Tyranny of forced father figure vs Professionalism

by Seaxereddington



Category: Assassination Classroom
Genre: Alternate Universe - Canon Divergence, Blood, Fluff, Karasuma is class Dad, Nagisa is still a badass, Torture, Worry
Language: English
Status: Completed
Published: 2020-06-26
Updated: 2020-06-26
Packaged: 2021-03-04 01:06:54
Rating: General Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,641
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24915088
Author URL: https://archiveofourown.org/users/Seaxereddington/pseuds/Seaxereddington
Summary: Nagisa knew he shouldn't take the knife but he couldn't even begin to quell the hate without teaching this man a lesson. A lesson he desperately needs. He felt bad but this was for the best... Wasn't it?But before he could steel his mind Karasuma sighs, shaking his head, "Takaoka please, allow me to take his place", he grit his teeth, "I can't allow him to even hold that knife".
Relationships: Class 3-E & Karasuma Tadaomi, Karasuma Tadaomi & Shiota Nagisa
Kudos: 63





	Tyranny of forced father figure vs Professionalism

**Author's Note:**

> This is just a one shot, might have a second chapter I don't know, but a what if "Nagisa didn't fight him?", and what would happen. I don't really know, and my opinion could totally be wrong, but please don't be so mean.
> 
> EDIT: I decided to re write it but I didn't want to get rid of this.

"Nagisa-kun... Will... You do it?", the uncertainty was clear in his voice. As well as strong worry. 

The knife before him glinted in the gloomy sun light.

Nagisa knew he shouldn't take the knife but he couldn't even begin to quell the hate without teaching this man a lesson. A lesson he desperately needs. He felt bad but this was for the best... Wasn't it? 

But before he could steel his mind Karasuma sighs, shaking his head, "Takaoka please, allow me to take his place", he grit his teeth, "I can't allow him to even hold that knife".

Korosensei gasped, standing up, ( _What?)_

( _What is he thinking?!_ ), Irina bit her fingers.

The class gasp, "What?", Nagisa stared at Karasuma's back, wide-eyed. "S-sensei!", he protested but Karasuma ignored him, standing tall. "Let me fight in their place, please".

Takaoka gaped for a bit, then a smirk over took it, "Haha... Haha hahaha!", he ran a hand through his hair, eyes crazed, "I never thought you would be this attached to them!", he continued to laugh, mocking their teacher.

The students felt a rise of spite grow, glaring at the chubby man. "Fine then. You love is touching you know, and I'm feeling pretty generous", he grinned widely, looking down on Karasuma.

"Fine, just kneel down to me and ask", Isogai gaped, "No sensei! Don't do it!". Kurahashi glared, running towards the teachers before being held back by her classmates, "Stop it Kurahashi!", Nakamura called.

Nagisa watched in fury as Karasuma kneeled on the floor, "Please Takaoka, I'll give you a handicap if you want", he looked, only to be faced with a strong shoe to his face, "Hey now!", the sickly sweet voice disgusted him.

"I didn't say you could look up yet", Karasuma looked back down feeling a warm liquid run down his nose. Small blood splatters stained the dirt.

"Well, since I'm feeling good today, I will allow you to fight me in their stead", Karasuma got back up, "But here's the catch", Takaoka took out back the real knife, "You give me five, whole minutes to attack with this knife while you're disarmed", he licked his lips, "Then the real fight starts".

Maehara tried to stand up, but winced, "N-no, it's not worth it Karasuma-sensei", he gasped out. 

But they were ignored. Karasuma looked back, feeling a rise if anger upon seeing their graces of despair and pain, fear. _Such faces didn't suit them. They should be smiling and enjoying themselves._

He would do whatever he needed to protect that innocence. He wouldn't die, and he would certainly defeat Takaoka. 

Said man grinned widely, expertly flopping the knife in his hand. "Let's make one thing sure", he nodded to the kids, "If anyone of them interferes, I won't hesitate to move them away".

Before they could protest, Karasuma spoke up, "You heard that? Don't interfere, this is for you all. I'll be fine", he reassured.

They moved back, albeit dejectedly, and he hated forcing this on them. He felt like a monster, but there was an other one to defeat right now. He would show Takaoka that no matter what happens, when it comes to fighting he will always be above.

At least, that's what he hoped. Yet the man had a real knife, and he only had his hands and legs. That put him at a severe disadvantage. As well as 5 minutes for his oppoenet to mess him up real good.

Karasuma braced himself, standing straight as Takaoka lashed at him, "Here I come!!", the fist collided strong on his face, pushing back but not off balance. The next kick threw him to the floor, a fierce aching in his stomach. Before he could even move a knife embedded itself onto his hand. Karasuma bit back a grunt of pain. 

Laughter filled his ears, "Oh? Done already, Karasuma?", the taunt did nothing, and he stood up, pulling out the knife from his hand and throwing it back to his opponent. Said man caught easily grin widening at the blood.

A strong scent of blood filled his nose, and the warm yet cold liquid freely flowed from his hand. 

Nagisa felt his fury burn as Takaoka beat Karasuma mercilessly. Before the man could even get back up he would already be on him, punching, kicking, stabbing.

3 minutes passed. Two remained. 

Karasuma lay in the ground a small pool of blood forming around his stomach as he panted heavily, attempting to get back up. 

3 minutes and 30 seconds passed. 1 and a half remained.

Takaoka's foot pushed down harshly in the wound forcing a cough of blood from the P.E teacher.

4 minutes passed. Only one minute remained. Takaoka drove his knee into Karasuma's face, said man spluttering blood onto the ground. He slashed the knife again, and more blood was shed.

4 minutes and 50 passed. 10 seconds remained.

Takaoka got ahold of Karasuma's arm, and in the next 10 seconds, he heard a sickening crunch as the arm was bended in ways it shouldn't be. 

5 minutes passed. 0 seconds remained. 

There was no way Karasuma could win, with such damage. Still, the man was on all fours arms, ( _arm)_ shaking violently, holding up his bloody form from the ground. "Well? Time's up! You can fight now Karasuma!", the knife wielding manic screamed, reigning in his laughter.

Korosensei felt his blood boil, while Irina glared with the coldest hate she could ever even muster. The students watched with gear as their teacher struggled to stand up. Nagisa narrowed his eyes coldly, hands twitching to grab the knife, and drive it in Takaoka's neck. Again and again.

Just as Takaoka lunged with the knife again, Karasuma felt a rush of adrenaline, and his left hand caught the incoming knife before twisting it out, feeling a wave of pain in his arm.

The chubby man let out a yelp, the grip getting stronger and stronger, crushing his hand. He wrenched it free, before sending a punch. Karasuma dodged, barely, and sent a kick of his own, the pain no longer their. 

He was in too much pain to even feel any more pain. But the fatigue certainly wouldn't disappear. The shouts of worry from the students fueled his adrenaline. A small grin made its way onto his face, "Prepare yourself, Takaoka. I won't go easy on you", before the man responded he sent a strong and quick round house kick to his face.

The man fell to the floor, holding his bleeding nose. Karasuma clutched his right arm, feeling a rush if pain from it ,knees weakening, before noticing a small glint on the floor. The knife gleamed, blood all over it. He picked it up, _that could have been some of their blood,_ his thoughts moved to the students.

_They could have been here. Nagisa could have been here. But he couldn't have that._

Takaoka got up, and a very real knife thrust itself in front of him, before quickly slashing his cheek. The glare was something else. The grin terrified him.

An other impact sent him flying, the urge to throw up the sweets from the before almost overwhelming him. But before they could carry on, Nagisa stood in nwteen them, "Sensei please stop!", he called.

Both men startled, as well as the others, (Students, octopuses and assassins of course). "I'll finish him off, Karasuma-sensei. It was his original request".

Before Karasuma could protest, Takaoka chuckled, getting back up and slightly clutching his stomach, "Sure why not, it was what I asked for, let's call it a draw. So let's test out teaching instead", he pointed to the knife Karasuma held, "Give it to the student who'll fight me, go on! Pick!".

Damn, he had no choice now, out of everything that had to happen the situation he wanted to avoid appeared. He surveyed the students, a lot of them watching in fear after the previous events. "Don't worry I'll give them the knife, and I'll be bare handed. They don't even have to cut me, they can just stop right before and it'll count", Takaoka stated arrogantly. 

Karasuma sighed, walking over to him, the boy giving him a steeled look of determination. "Then.. *cough", harsh coughs erupted from his chest speckles of blood falling to the floor, "I trust you'll be okay?", he heard their gasps. Whispers of disbelief and confusion spread through the students. 

Nagisa nodded, fury burning in his cold, azure eyes, "Yes sense, I'll do it", as he grabbed the knife, Karasuma couldn't help notice how slender and small his hands were. Yet they held the knife so confidently. 

Nagisa stretched, while Takaoka laughed, "Karasuma, is your eyes sight going bad? This little runt?". 

"Remember, Takaoka wants to make you an example, but this is an assassination for you. Just hit him once, and you'll win", he stated wincing a little at the pain from the bending down a little. 

The blue haired, petite boy nodded, holding the knife steadily. 

The anger in his chest wouldn't disappear, but he didn't know how to quell it. _He can't just go in and attack, that would be worse than Karasuma-sensei._

Nagisa's eyes trailed back to the teacher and the two students who had been hurt earlier. A bruise had formed on Kanzaki's cheek, while Maehara clutched his stomach in pain. 

He watched as Karasuma-sensei's legs gave out, and the teacher collapsed to the ground. The students called his name on worry. 

_That's right, I just have to kill him._

So he walked to him, like an other school day. And lightly bumped into the teacher's arm. Said man was confused, before he barely dodged the knife slash. 

Takaoka startled back, and Nagisa grabed his shirt and pulled down. He then slithered like a snake behind him, earning screams of fear from the chubby man before pouting the knife in front of his neck, "Got ya", Nagisa simply said, a confident smile dancing on his lips. 

Silence filled the atmosphere. The students gaped, while Korosensei nodded in pride. Irina's eyes were shocked, while Karasuma gaped in absolute shock. _Unbelievable,_ feeling a wave of dread, _the chill I felt, was because I imagined a real assassination._

 _That isn't talent for fighting, but talent for assassination._ It would be fenomenal for this class if such talent was nurtured. But could he really do that? Should he really nurture such talent?

"Whoops, was I supposed to use the back of my knife?", Nagisa sweated, blocking a few times. A yellow tentacle reached over and grabbed knife before Korosensei ate it, "Geez, how dangerous it was to give him the knife, what if he hurt himself? ", a tentacle pushed Karasuma's back gently, keeping him up. He let out a low groan, feeling his mind go hazy, and black dots decorate his sight. 

"Right, my bad", he mumbled, but smirked, _You would have been there at mach 20 to patch him up._ Maehara walked up to hon, before slapping him. "Ow! Why?", Nagisa asked, holding his cheek. 

The boy laughed, apologising before explaining how he was worried it wasn't him.

The octopus placed his head on his shoulder, "You were pretty lost out there today Karasuma-sensei", he laughed. 

The male teacher grimaced, "There a problem... With that?", he huffed, taking in deep breaths. 

The kids rejoiced, before noticing Takaoka's towering figure., "You little brat! I was like a father to you! How dare you defy me! Why are you happy over a lucky win like that?!", he snarled, "Let's have a rematch! I won't let my guard down this time! I'll crush your mind, your body, your spirit-- everything!". 

Karasuma felt a rush of adrenalin, getting up to stop him until a tentacle stopped him. Nagisa faced Takaoka, "Right, I would probably lose if I fought you again. But one thing is clear now, Takaoka-sensei". 

He stood proud and strong, along with the other students, "Our teacher is Korosensei, and put P.E drill instructor is Karasuma-sensei. You can call yourself a father figure, but to my mind, Karasuma-sensei who behaves professionally is a lot closer to the real thing". 

Karasuma felt a warm feeling from the words.

Nagisa bowed, "I'm grateful to you for being serious about training us to become powerful assassins, but, we would like you to leave now". 

"The greatest joy of being a teacher, Karasuma-sensei, is when a student provides a clear answer to a question you had your doubts about", the target explained. 

Takaoka's face scrunched up, "No more... Mr Nice guy... How dare you.. Speak to a grown-up like that, brat!". 

The students backed up in fear, "Karasuma-sensei, if a students gives you clear answer, the teacher must acknowledge it", like a flash Karasuma appeared and easily elbowed Takaoka with a smile. _Payback feels nice._

He took in a deep breath, before letting go of his broken arm, "I'd like to apologise for all the trouble my colleague has caused you", he pointed to himself, "Don't worry I'll negotiate with the higher ups to allow me to become you only instructor. I'll get there authorisation at gunpoint if push comes to shove!", he stated boldly. 

_It's dangerous, but better than anything that had happened previously. He was seriously considering pulling out a gun if they didn't let him. Then again I could use the fact he's willing to kill colleagues as leverage._

"Karasuma-sensei!", the students called out. 

Said man winced a little, feeling blood pile in his mouth. 

Takaoka growled from the floor, "I'm... Won't let you! I'll talk to them be--", a cool and husky voice cut him off. 

"Thee is no need for you to attempt that negotiation", the students and teachers looked back in shock, "Board chairman Asano?!". 

The principal walked to Takaoka on the floor, before speaking some harsh and cold words, before shoving his dismissal letter in his mouth before walking away while wiping his hands, "Fhe ministry of defense has no authority to appoint the teaches who work at this school. Please don't forget that. Everything in this academic institution is under my auspices and at my discretion", he turned back to look at Karasuma from the corner of his eye, who had sat down from the pain, "And I have called for an ambulance. It will be here soon". 

"Thank you", Karasuma nods. 

Takaoka suddenly screams before grabbing his bag and running away. 

The students cheered, as Korosensei grinned, "He's as confident as ever in his views", the target said. 

Karasuma wanted to ask a question, but felt his energy sapped from him, his eyesight once again going black at the corners, "If.. If he said... He wanted to... Be an assassin... Would you still support him?", the exhaustion was apparent in his voice. 

The beady eyes of his target softened upon gazing at the young boy who had expertly wielded a knife not too long ago. "That'll be a conversation for later once you have recovered". He picked up Karasuma's right arm, and stretched it a little. 

Karasuma made a noise, then bit his tongue, "That's definitely broken", a tentacle prodded at his stomach, earning a small yelp of pain, "And that needs looking at". 

Korosensei's grin softened, "Thank you, for worrying so much. I'm sure they appreciate it". 

The students looked at him, worry evident in their eyes. He smiled slightly, taking out his wallet, "I don't know much about sweets, but I'll supply the money", he coughed a little, earning some gasps of fear, "But I'm afraid I'll have to join to next time". 

The last thing he heard and saw was the students calling his name, their faces of worry, and Irina's knowing smile. 

The wallet slipped from his hand as he fell back. 

He swore he could've heard her mutter something like, " _Softie",_ through the sirens of the ambulance. 

**Author's Note:**

> Just a one shot that u wanted to try, so uh year sorry Nagisa fans if I upset you, but trust me what originally happened still happened, but with a difference of what might have happened, like the other story of what if Karasuma lied to the ministry if he tried to protect Korosensei


End file.
